While there are many reprehensible aspects of the Castro government in Cuba, from an economic point of view, it has been far more successful than its capitalist neighbors. According to a CIA report, Cubans enjoy a far higher standard of living than most countries in their immediate vicinity:
Cubans do much better than the citizens of all their neighboring Caribbean and Central American states by all kinds of measures. The Cuban government spends much more on education, and a Cuban child therefore can expect to get a much better education, and for several years longer, than a child in any of Cuba’s neighboring countries. A Cuban citizen can expect to live longer. Cuba’s GDP per capita is higher than it is in seven of its nine neighbors. Cuban workers also fare better than their brethren in the U.S. because, while the GDP per capita in the U.S. is significantly higher, Cubans, until this month, have enjoyed universal job security and virtually no unemployment. How can Castro and the CIA see things so differently?
The myth that western style capitalism works around the world simply does not stand up to scrutiny. Firstly, western economies are highly protectionist and rely heavily on state planning and intervention for economic growth, contradicting the basic tenants of the 'free market'. The economic system we export around the world has little to do with our own, and more to do with the need to expand our own markets. Protectionism and regulation are bad because they prevent western companies from entering and exploiting third world markets (like Cuba), so must be vilified rigorously. 'Capitalist' countries like Jamaica are good because they don't interfere with western countries exploitation of their natural resources, despite it's devastating effects on the population.
The myth that capitalism works and socialism doesn't relies on rampant propaganda from economic elites - the beneficiaries of government bailouts and massive protection of their industries (most people on Wall St would not have a job right now without the aid of the federal government). Socialism exists in America, but only for the rich, while the free market is for everyone else. The we must hear lectures on its efficiency despite its obvious failures is a symptom of the media's failure to provide serious analysis.
So the myth pervades that Cuba and other countries that refuse to allow their resources to be exploited by the west are failures, while those that do are a massive success.